Conclusions: :
LAD2 express ARs in the order A2A>A2B, A3, but A1 was undetectable.Non-selective activation of ARs with NECA enhances degranulationstimulated immunologically or by C3a. Selective AR inhibitionreduced the enhancements, with A2A≥A2B>A3. Ecto-enzymaticmetabolism of autocrine-released ATP is not a significant sourceof adenosine. We conclude that mast cell degranulation can bemodulated by ecto-enzymatic dephosphorylation of ATP found ininflammatory milieux, largely through A2AR.